On this day

20 October in history.

5 moments from 1781 to 2003: discovery, creativity and courage, each with a source to read more.

5 moments

SLAC and its neighborhood, where it stands out as a long straight feature.

1969

Scientists find the first signs of quarks. Results from the Stanford Linear Accelerator Center showed that protons are made of even smaller particles. It was the first evidence for quarks.

Wikipedia: SLAC National Accelerator Laboratory

Photo: Dicklyon / Wikimedia Commons (CC BY-SA 4.0)

More from 20 October

  1. Patent of Toleration , front page top: Patent, Wegen der den augsburgisch und helvetischen Religionsverwandten, dann den nicht unirten Griechen zu gestattenden christlichen Toleranz und ihres privat excertii Religionis. ["Patent aimed at the members of the Lutheran and Calvinist…

    1781

    Austria allows more freedom of worship

    Austria approved the Patent of Toleration, giving people a limited freedom to practise their faith.

    Wikipedia: Patent of Toleration

    Photo: Joseph II, Holy Roman Emperor / Wikimedia Commons (Public domain)

  2. 1910

    The ocean liner Olympic is launched

    The British ocean liner RMS Olympic was launched.

    Wikipedia: Ocean linerWikipedia: RMS Olympic

  3. Sydney Australia.

    1973

    The Sydney Opera House opens

    After 14 years of building, the Sydney Opera House was officially opened by Queen Elizabeth II.

    Wikipedia: Sydney Opera HouseWikipedia: Elizabeth II

    Photo: Bernard Spragg. NZ from Christchurch, New Zealand / Wikimedia Commons (CC0)

  4. Three-dimensional DTFE reconstruction of the inner parts of the 2dF Galaxy Redshift Survey . The figure reveals an impressive view on the cosmic structures in the nearby universe. Several superclusters stand out, such as the Sloan Great Wall, once known as the largest structure…

    2003

    Students discover a giant wall of galaxies

    Students at Princeton University discovered the Sloan Great Wall, at the time one of the largest structures known in the universe.

    Wikipedia: Sloan Great WallWikipedia: List of largest cosmic structuresWikipedia: Princeton University

    Photo: Willem Schaap / Wikimedia Commons (CC BY-SA 3.0)

Moments chosen for discovery, creativity and courage. Each one links to a source where you can read more; photos are credited to their owners.